PVC Bulletin May 2007



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Potomac Valley Chapter

North American Rock Garden Society



Volume 9, Number 3


May 2007


This bulletin is a bimonthly publication of the Potomac Valley Chapter, NARGS

Jim  McKenney , Editor   jimmckenney@jimmckenney.com  301-770-1867

Next deadline: June 15, 2007

Image Gallery May 2007: Eighty Images This Time!

Calendar 2007 & 2008

It's time to pay dues for 2007! Send your check for $15  to Margot Ellis, 2417 N. Taylor St., Arlington, VA 22207

May 19 Our plant sale at Green Spring Garden Park. Contact Jim Dronenburg to volunteer to help. Jim says:

Setup will be on Friday the 18th at noon.  Merry Bruns has once again volunteered to get the tent—who has the signs?  -- and help is always welcome on Friday to price plants and generally give moral support and have fun. 

The Green Spring Garden Day will open at nine, hopefully people (including me) will be there at eight to combat (or indulge)  the gate crashers.  Please give me (Jim Dronenburg) a call at work in Silver Spring 301 578 8914 – or at home 301 834 6515—to volunteer for whatever time you can give.  And start potting things up!  Label them, please, and if possible give a yell what you will be bringing and if you will need help with portage from your car. 

The Plant Exchange will be the DAY AFTER GREEN SPRING, SUNDAY May 20th

May 20 Our chapter plant exchange. To take place at Alcova, 3435 8th St.,Arlington, VA. Coffee at 9:30; plant exchange begins at 10 a.m.. Note that this year the plant exchange is taking place the day after the Green Spring event, not the week after.

June 14-17, 2007 Canaan Valley Resort State Park, West Virginia, 2007 NARGS Annual General Meeting, Chairperson  Martha Oliver, 921 Scottsdale-Dawson Rd., Scottsdale  PA 15683

July 14, 2007 our annual picnic , home of Bob and Bobbie Diebold, 505 Foxhill Road, Front Royal, VA, 540-635-9635

Bobbie invites us to arrive anytime after noon to allow time to enjoy the garden; the official starting time will be announced in a future PVC Bulletin as will driving directions.

October 7, 2007 Janis Ruksans will be here on October 7 (Sunday) at 9:30, place TBD. 

November, members' slide show; time and place TBA

January 12, 2008 Allen Bush of Jelitto Seeds, time and place TBA

February 2008   Sasha Borkovec, time and place TBA

March 15, 2008 Roy Klehm of Klehm's Song Sparrow Farm and Nurseries  speaking on the smaller peonies. USBG, time TBA

November, 2008, Karen Rexrode, time and place TBA




Kathy and Bob Rushing, Silver Spring, Md.

Returning member:

Michael W. Cassidy Alexandria, Virginia


The Expanding Garden

What Will Happen to Your Garden 

When you move into the house in which you expect to spend most of your life, you will sooner or later begin to develop the garden.  If you are sensible, what you plant may be fairly modest and easy to maintain.  But if you are like us, you have (or will have) gone way beyond that.  At some point, you will face the issue of how to fit more plants into a finite space, no matter how much land you have.  If you are really stuck then you may get creative by using space that you don’t actually own, such as roadsides, median strips, a neighbor’s land or even a public park. 


If you have expended a lot of time and effort creating your garden then eventually you must consider its future.  For very few of us there will be a natural succession, such as an offspring with an offshoot of the same kind of interest.  But typically, the garden will fall into the hands of strangers for whom our exuberant plantings may be impediments or just too much trouble to keep up.  As one of our helpers on the YMCA last summer said to another helper, “they grow all of these plants and none of them are edible, and some aren’t even attractive”.  I think that that is likely to be the attitude of those who wind up with our land and everything that we have planted on it.


On a recent visit to Alice Nicolson’s garden, someone asked her about a flowering camellia near the front steps.  “I don’t know which one that is,” said Alice, “that was here when we bought the house more than 40 years ago.”  On another occasion, in Jim McKenney’s garden, he pointed out an evergreen shrub that had splayed out in all directions.  “That’s Cephalotaxus harringtonia ‘Fastigiata’, he said, “it’s 40 years old”.  I cite these two examples to show that gardens can become quite ‘mature,’even within our lifetimes, although they still keep changing.  We have raised mature trees, including some from seed or tiny seedlings, in our more than 20 years of living and gardening at the same site in Alexandria, Virginia, so we too have had some longtime companions.


With recent thefts and vandalism in our gardens on the YMCA and in the adjacent Simpson Park, we have begun to seriously reconsider whether we want to continue living in the same house after I retire.  At one time we thought that living next to these public gardens in which we could potter around when I had more time and when my wife had given up her landscaping business would be ideal.  I could indulge my fondness for growing and pruning unusual woody plants and she could employ her sense of design to improve the gardens.  And we both would  enjoy the goodwill that is regularly expressed to us by people from the community as they walk by, watch their children playing baseball in the park, or come out to their cars after exercising in the YMCA.


This year a different kind of reality has taken hold of us.  It has always been evident that we cannot maintain the public gardens by ourselves.  The gardens in Simpson Park were installed by Master Gardeners of Northern Virginia and, in theory, are maintained by them.  In practice, there never seem to be enough Master Gardeners at work parties to keep up with all the maintenance.  People from the community help us with the gardens on the YMCA.  But with few exceptions, work parties for the Y gardens have been poorly attended.  For example, we had a work party on Earth Day this year (Sunday, April 22) and only two people came. Thus much of the work falls on my wife and me, and we simply cannot cope.  “Do we want to live next to these gardens and watch them deteriorate?” is the question that we have been asking ourselves.


We have always had to deal with some thefts and vandalism.  I suppose that it is the bane of all public gardening.  But this winter and spring the vandalism and thefts have been particularly galling.  I won’t go into detail: it would be too depressing for you and for us. The director of Kew once told me that they had trouble keeping certain annuals going from year to year because people steal the seeds.  A retired curator at Kew once cautioned me not to judge all British gardens from the private gardens near Kew.  Either the local gardeners are inspired by their visits to Kew, he opined, or else they ‘nick’ bits of Kew plants for their own gardens.  Hence the unusual diversity in these small spaces.


This year, on top of everything else, the weeds have been overwhelming. The beds looked – and still do in many places – as if the gardeners who maintained them had moved away or died.  The weeds – mostly chickweed, dead nettle and bitter-cress – completely covered the ground, including low bulbs and rosettes of perennials.  In places they also seemed to be climbing up shrub and tree bases.  Many have already matured, having shed enough seeds to allow for their tenfold (or more) increase next year, unless we take measures to prevent germination.  But even the moribund weeds need to be removed, and we can’t do it all.


With all of the maintenance, vandalism and theft problems that we have had this year, one might anticipate that we would have refrained from purchasing many new plants.  Far from it.  We have attended four plant sales in the past three weeks, and the plant trays runneth over.  Are we just compulsive or are we secretly optimistic?  Probably the former, but if we can just get past the horror of the weeds, perhaps the glass will start to look half full again, at least until next summer’s drought.

Robert Faden                                                                                                                                                                                                                                                             

Two brief reviews by Robert Faden


“A xeric fern rock garden” by David Schwartz (Fiddlehead Forum, vol. 33, no. 5: 25-29).  This article in the Fiddlehead Forum, also known as the Bulletin of the American Fern Society, is a very interesting account of how the author learned to grow xeric ferns from the southwest and Mexico in a rock garden at his home in Napa, CA (about one hour north of San Francisco).  Considering his climate - extreme heat in summer and only six and a half inches of rain annually - I don’t expect that many of the 66 species of ferns that he lists as currently growing in his garden would succeed here, but I suspect that there are some xeric species that would be succeed in our area if someone cared to try them. 


This article is followed by another by Tom Stuart (tstuart@westnut.com) entitled “Fern sources” (Fiddlehead Forum, vol. 33, no. 5: 29-31), with an unusually thorough list of sources of ferns (hardy ones as well as tropicals) in the U. S.  For every source he furnishes a rough idea of the extent of the fern offerings and a mailing address.  Unfortunately, for the most part websites, e-mail addresses and telephone numbers are not given.  For some sources he lists a general price range, such as for Glasshouse Works “$4 to jaw-dropping”.  The fern sources are listed under groups, ‘All Ferns All the Time’, ‘Specialty Nurseries’, ‘Perennial Nurseries with Unusual Fern Offerings’ and ‘Odd Lots’.  Overall, this is a very useful article if one is looking for sources of ferns for gardens or greenhouses.



Rock Garden Peonies


Several threads come together in this piece. A few weeks ago Dixie Hougen and I exchanged emails on the topic of Paeonia tenuifolia. Dixie was trying to trace the origin of a plant known to have been growing in Augusta County, Virginia (as it was then delimited)  during the nineteenth century. That’s all I’m going to say about that one: maybe sometime in the future Dixie will want to tell the whole story. Dixie’s plant is almost certainly a hybrid of Paeonia tenuifolia or P. anomala. Take a look at it in the May image gallery: Dixie's Mystery Peony.


Paeonia tenuifolia itself is small as peonies go; most of the wild forms are in the 12-18 inch range. They are noted for early bloom and finely divided foliage. In addition to forms collected from the wild, hybrids have appeared in gardens. Back in the ‘70s of the last century I received from the Louis Smirnow company Paeonia × smouthii; this is  a hybrid which  seems to have first appeared in the early nineteenth century and is believed to be a hybrid of Paeonia tenuifolia and P. lactiflora. I no longer have this plant. Years ago Bobbie Lively-Diebold and I were touring her Fairfax County garden and we came on a plant which looked a lot like my  Paeonia × smouthii, although it was a bit bigger. Bobbie thought her plant had been received as Paeonia anomala, a variable species some forms of which do resemble Paeonia × smouthii.


Several weeks ago I made a quick stop at Behnke’s Nursery to look for a garden peony on my want-list which they have sold in the past. I didn’t find what I went out for, but I did find something interesting. I came home with a plant of Paeonia ‘Lil Sweetie”, another Paeonia tenuifolia hybrid.  See the images in the May image gallery: Paeonia 'Lil Sweetie', Paeonia 'Lil Sweetie'

 Washington Post staff writer Adrian Higgins did a piece on tree peonies recently. In that piece he mentioned the Klehm Song Sparrow nursery. It had been years since I last saw a Klehm catalog, so I checked out their web site. There I was tickled to discover that they have grouped several low growing Paeonia cultivars a “rock garden peonies”. Most of them looked like hybrids of Paeonia tenuifolia.


For many years I have grown a now half-century old cultivar known as ‘Early Scout’; this is another hybrid of  Paeonia tenuifolia  and P. lactiflora. This grew for years, too many years, at the eventually shady end of a long border here. As a result, it went into decline and had not bloomed for a long time. In the autumn of 2005 I dug all the pieces of this plant I could find and replanted them in a spot with full sun. This year they are up and budded, and when they bloom it will be for the first time in over a decade. It is this plant in particular which I have thought of as a rock garden peony for a long time. It forms low (18”) mounds of handsome, finely cut foliage. The foliage is coarser than that of Paeonia tenuifolia, but the plant is a lot easier to grow well. The flowers, as with almost all of these Paeonia tenuifolia hybrids, are bright red and what we gardeners call single (i.e. normal flowers). This, too, is shown in the May image gallery: Paeonia 'Early Scout'


In our climate, peony flowers with few petals are of fleeting duration. All of these early blooming red peonies are handsome and eye-catching in the garden, but they have another quality which makes them valuable garden plants: the mounds of finely dissected foliage are reason enough to grow these interesting plants. Seed of the various wild forms of Paeonia tenuifolia  sometimes appear in the lists; these wild forms vary in height and degree of dissection of the foliage. This variation might in the future provide hybridizers with more to play with in developing yet more of these hybrids. 


Here’s a story about the fleeting blooms of some peonies. Several years ago a friend was thoughtful enough to invite me to accompany her on a visit to Nancy Goodwin’s garden  Montrose.  That visit was written up in an earlier PVC Bulletin. It was a relatively long visit, and it was only at the end of the tour that we came upon a splendid clump of Paeonia mlokosewitschii. The soft yellow petals were scattered on the ground: not a single bloom was intact. In retrospect, I can not help wonder if we had jumped out of the car on arrival and dashed over to this plant if we would have seen it actually in bloom.                Editor


Some Rock Garden Tulips


Bulb lists these days offer a fascinating array of tiny tulips which are right in scale with our expectations of rock garden plants. Many of them are inexpensive, and more and more appear yearly in local retail outlets. For the rest, there are mail order outlets. Aside from their intrinsic interest, their main value in the rock garden is the same as the main value in the greater garden of the big tulips: they provide lots of interest and color before the main burst of most other herbaceous plants 


These small-bulbed tulips have something else going for them: they persist in gardens indefinitely if, and this is a very important if, they are planted in a well drained soil. Better yet, plant them where the soil can be kept dry during the summer (under a cover of some sort, for instance). In the autumn of 2003 I built a raised bed for summer dormant bulbs. This bed is a long (18’), narrow (30” at most) eighteen inch high bed which gets as much sun as any spot in my garden. To celebrate the completion of the bed, I mail ordered a few each of as many inexpensive, so-called species tulips as I knew sources for. Those plants are now in their fourth spring, and the display gets better yearly. But for one important practice, these plants are care free. The one thing I do is to cover them in late May and keep the bed covered until sometime in September. The covers are discarded 6’ × 3’ glass sliding doors – in effect cold frame sash but comparatively heavy. 


This raised bulb bed is prime real estate in this garden: there is no reason to grow there something which will survive in the open garden. Right now its tenants include a single  Eremurus (a very big single Eremurus),  irises (reticulate, juno and arilate sorts), choice crocuses, some fritillaries, odds and ends in the Muscari-Bellevalia group, orphan colchicum being grown on to blooming size and -  I hope - an identity, some Allium and the tulips.


The image gallery shows some of these tulips. Some bloom very early, some bloom mid-tulip-season, others are late blooming. Throughout March, April and early May there is likely to be something in bud or bloom. The peak comes in mid-April and early May.


Several of these tulips are stoloniferous. They are capable of forming extensive patches over the years. Generally, these patches are like patches of our native trout lily, Erythronium americanum: one flower to every several dozen leaves. But they are as carefree as anything in the garden when properly sited. Four which are notable in this respect are Tulipa sylvestris, T. whittallii, and two forms of T. clusiana (one, long known as Tulipa stellata chrysantha is now known as T. clusiana chrysantha; the other is the plant originally and for centuries grown as Tulipa clusiana. This plant is now in a sort of nomenclatural limbo because the name Tulipa clusiana (with various qualifications) is currently used for a number of tulips.  The “old original” form does not have widely used name other than, confusingly, Tulipa clusiana.


Two groups of these little tulips have been well developed by hybridizers: one centers on Tulipa humilis and the other on Tulipa batalinii/linifolia.


The humilis group is perhaps one of the really underappreciated tulip groups: the flowers are smaller than those of garden crocus, but come in a very pleasing range of  mostly pinks but some whites and reds. Exterior markings when present can be green and bronze, and there are  generally contrasting interior markings.


The tulips of the batalinii/linifolia group have a distinct flower form: in effect, they are miniatures of the big greigii and fosteriana tulips. The color range is more limited here, mostly yellows ranging from very pale to chrome yellow, with some sorts marked with bronze. The red forms are likely to be forms of Tulipa linifolia, or T. wilsonii or T. maximowiczii (the names used here are the ones you are likely to encounter in trade lists). Although tiny, these all have a perky stance which is distinctive and eye-catching.


Two other clones deserve mention: ‘Little Beauty’ and ‘Little Princess’. ‘Little Beauty’ will remind you of the members of the humilis group, although it blooms later. ‘Little Princess’ has the rich orange color of Tulipa whittallii and T. hageri. Take a look here: Some rock garden tulips


In order to justify my sometime profligate spending on bulbs, I play this game: I amortize the expense over the years the bulb lives. Thus, with the tulips in the raised bed, I now figure that since they are in their fourth year of bloom, the cost per year is one fourth of the original cost.  The cost in the first year was of the I’d-better-not-mention-this-to-anyone sort; but now four years later it’s already down to the movie-and-dinner (without wine) level.  And that’s not taking into account increase.


Do try these little tulips. Plant them in the garden if you must, but try to keep some in a place where you can get close to them to appreciate their abundant but small-dimensioned charms. If you try them in pots, remember that they respond well to plenty of water when in active growth – let them dry too much and the flower buds will fail and the plants quit for the year. They are well proportioned for troughs, but again remember their moisture requirements (as long as the soil is well drained, lots when growing, none when not).                                                                                                                       Editor






President                              Paul Botting           301-869-3742     pmbotting@comcast.net
Vice President                      Jim Dronenburg     301-834-6515     rutlands@adelphia.net
Secretary                                Sandra Carlson      703-548-3825
Treasurer                                Margot Ellis           703-312-1147     margotellis1@yahoo.com
Immediate Past President    Alma Kasulaitis     703-312-1147  amkasul@starpower.net


Committee Chairs:

Archives and History                                          Jo Banfield                            301-762-6771

Communications                                                  Alice Nicolson                      703-979-5871

Finance                                                                  Margot Ellis                          703-312-1147

Membership                                                          Linda Keenan                       301-434-9671

Program, Education & Outreach                        Betty Spar                             703-549-0214